I for one would like a bit more short/mid-length hair. The miqo's have some pretty nice options, but the others don't have the same (I'm thinking of the Hyur's in particular). The haircut I have on my avatar is nice, and I'd like to see some equivalents. I feel like I'm going against the grain a bit, but I'm also tired of the bows, curls and braids they keep throwing at us. Like... this haircut for example:

https://ffxivcollect.com/hairstyles/66

Why the hell did you put a knot in it? It's... (<beginning of personal lament) ugly and so damn girly. Just... give me more simple options, that don't look like the person just came out of an extra elaborate blowout, or a makeup session with their 15 year old girlfriends.

In the same tone, a little more attention to hairstyles for men. Especially for beards, which don't have enough options.

Edit : ah, with one exception : Hilda's hair, I'm a fan as well.